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Sprinkler cuts off water to house every other use

I had sprinklers installed last year near the end of the season. As soon as the installers left, I turned on my kitchen faucet to wash off a plate and had no water pressure at all. I called the installer right away and he said to leave the faucet on and turn on the sprinklers. The water pressure returned and I hoped it was just a one time problem associated to the install. For a week later, I let the sprinklers run every morning to encourage the grass to heal where it had been dug up and had no problems.

After that I switched to a twice a week schedule and the problems began. Like clockwork, every other time I run the sprinklers the water to the house is shutoff after the last zone finishes. To get it back on, I open a faucet, manually turn the sprinklers on for a few seconds and then off and water pressure is returned to the house. Before it was winterized last year, the installers came out and removed the main water cutoff in the basement of my house to inspect it for debris and it was fine. This year the problem continues. I should probably also mention that because of the layout of my basement, they had to connect to the water supply at the street and not in the house. Also, the "every other time" behavior also occurs if I manually kick off the sprinklers instead of scheduling it on the timer.

I have a meeting tomorrow where I suspect that this is going to get thrown back in my lap as a plumbing problem in my house which is only 3 years old. Has anyone ever heard of any problem like this? Is there any likely culprit that I can ask the installers to look into? They say that they have never had this problem and always install the same way they did in my yard. My neighbor used them as well and is having no problems but they tied into the water supply in his basement as opposed to out at the street. Thanks in advance for any tips you might have! This is driving me crazy.

There is a backflow preventer outside by the side of the house. No changes were made in the basement other than inspecting the main cutoff for debris and putting it right back a couple weeks after the initial install.

You may have a jam in the backflow preventer, assuming this is a preventer feeding the house plumbing. If the sprinkler tie-in is upstream of the preventer, then pressure in the house plumbing will be higher than the pressure upstream of the preventer. when the sprinklers run. That is a condition that was never there before the system was installed.